The present invention relates to a management method for a memory region shared by a host OS and a guest OS managed by the host OS or another host OS in a computer system in which a plurality of host OS run.
In recent years, as a means to effectively utilize the hardware resource in a physical computer, the technology of running two or more OS (operating system) in one physical computer is drawing attention (see Japanese Patent Application Laid-open Publication No. H11-149385 and WO/2009/113394, for example).
Japanese Patent Application Laid-open Publication No. H11-149385 describes “a multi-operating system computer configured to alternately operate to activate an active OS, a first OS (operating system) that executes a plurality of tasks with different priorities in the order of the priority levels and a second OS differing from the first OS as active OS, comprising an OS switching part configured to switch the active OS from the first OS to the second OS when a task that is a prescribed task with a priority among the plurality of tasks and that is used as a switching trigger task for identifying a timing of switching of the active OS is executed while the first OS is running as the active OS.”
WO/2009/113394 describes that Multi-OS boot device includes the first operating system (Operating System, hereinafter referred to as OS) in the multi-OS starting device for starting the at least two of the OS and the second OS, (1) a memory area, and the primary storage unit in which memory space is defined with respect to the memory area, (2) a second boot loader, a secondary storage unit for storing a second OS, (3) CPU and the fast boot loader operating under the first OS to a context of a control information operates in the first context is a context for the first OS to the (Central Processing Unit) By operating under said first OS running in the first context, with respect to the primary storage device by said first context as a first memory space for the first OS to manage and the OS execution unit to the memory area of the defined the primary storage unit from the secondary storage unit to load and said second OS and the second boot loader on the first boot loader, (4) said first one of said second and OS by executing the second boot loader loaded in the defined memory area as the memory space based on the first OS running in the first context wherein There defining a third memory space where the second of the memory areas is defined as a memory space the second boot loader and the second OS to be managed and a loaded memory area to the primary storage unit and let switch the context for the second boot loader from the second boot loader on the first context to context for the second boot loader, which is generated with generating, by executing the second boot loader in the original context for the second boot loader said second of said second OS loaded into the memory area of the primary storage unit in the memory area of which is defined said primary storage unit by the first boot loader as a memory space included in the third memory space said together to load the second boot loader to generate a context for the second OS, to generated the second context for OS let switching from the context for the second boot loader, the context for the second OS and characterized in that it comprises a loader executing unit for executing the activation of the second OS on the second boot loader under.
With this multi-OS technology, by installing a host OS1 as the first OS (host OS1), installing a hypervisor as the second OS (host OS2), and installing server control OSs as the OSs (guest OS1 to guest OSn) for a plurality of logical computers on the hypervisor, for example, the space and price of the device can be reduced.